On the original boards you set one relay at a time and cycle through them. All 16 take less than a quarter second.

Given that, the current on the 12v line shouldn't go much above the 17mA per relay. You should spec for higher by about 4x just for fun. Since they are latching there is only a small quiescent current when they are not switching.

I went back to look at some of the old posts and got nostalgic

will this be available for a GB ?

The files are posted on Kevin's boards site.

I've checked the boards, but wanted to test them so I just had s small run made.

These would be great candidates for assembly as well. It's surprisingly inexpensive.

I'm not sure if I would be up to running the group buy. It was quite a bit of effort. I would happily work with someone though.

Edited July 27, 201510 yr by Kerry

A question: since the relays seems to be the largest expense if building a few of these, would it make sense to go for a slightly larger but cheaper relay? For example:

http://se.mouser.com/ProductDetail/KEMET-NEC-TOKIN/EE2-45TNU/?qs=sGAEpiMZZMs3UE%252bXNiFaVLHF5q190qntaE86wsYZ%2ffA%3d

I'm not fully sure this part would work, so apologies if I don't have the spec right. If it does, it would make the board roughly 15 mm longer (bad) but save 25-30 euro on the relay cost (good)...

that is dual coil latching and would require the either the original board

or more layers on the new board

Right, my mistake! Looked at wrong spec after all.

Kemet single coils (http://se.mouser.com/ProductDetail/KEMET-NEC-TOKIN/UD2-5SNU/?qs=sGAEpiMZZMs3UE%252bXNiFaVF%2fhK9L3NJJAV11VD4%2fXV0g%3d)

were wrong voltage and 3,42 euro a piece compared to Omrons 4,00 euro (and even less difference at volume), so no point really. My apologies, thought I had it right.

A question: since the relays seems to be the largest expense if building a few of these, would it make sense to go for a slightly larger but cheaper relay? For example:

http://se.mouser.com/ProductDetail/KEMET-NEC-TOKIN/EE2-45TNU/?qs=sGAEpiMZZMs3UE%252bXNiFaVLHF5q190qntaE86wsYZ%2ffA%3d

I'm not fully sure this part would work, so apologies if I don't have the spec right. If it does, it would make the board roughly 15 mm longer (bad) but save 25-30 euro on the relay cost (good)...

Those look like they would work for the V1 PCB (in the proper 12V coil voltage), and are considerably cheaper ($2.31 10 or more, vs. $4.05 25 or more for the Omrons). Contacts are silver alloy with gold alloy overlay. Dimensionally they look very close and should work.

 

Not sure if the Omrons have any advantages to warrant the price difference? Are Omron more reliable? I know they have been in the relay game for a long time.

on the old boards, you need 2 boards for balanced.

 

the new board is balanced all on one board.

I just got these back and will try to build one this weekend

I've been using a hot air gun and solder paste. I'm really loving it.

 

That was fast. Looks good Kerry.

Nice.

Are the attenuator resistors 1206 or 0805, is there a reason for the larger mounting holes at the corners ?

Edited August 15, 201510 yr by b0bb

the holes are .125 inch, good for a #6 screw.

I can certainly make the holes smaller for production boards.

the 50 ohm resistors are the bigger ones, those attenuator

resistors are the smaller ones.

remember that the board is 2 x 3 inches, on my screen it shows up at about 2x

other than the 3 caps, there are exactly the same number of components on the back

of the board

Edited August 16, 201510 yr by kevin gilmore

the holes are .125 inch, good for a #6 screw.

I can certainly make the holes smaller for production boards.

the 50 ohm resistors are the bigger ones, those attenuator

resistors are the smaller ones.

remember that the board is 2 x 3 inches, on my screen it shows up at about 2x

Thanks for the clarification, at 2x3inches, it is just slightly larger than the footprint of the RK50, I am thinking of using this attenuator instead of the RK50 on my T2 build.

Quite an achievement cramming 16relays on the board but leaving enough space for hand assembly, the work is much appreciated.

The hole can either be made smaller or moved closer from the edge to allow the standoff the seating space to prevent it from wobbling.

Edited August 16, 201510 yr by b0bb

Looks great Kerry! 

If there is a GB for this, I like to state my interest for an assembled board option like the last one Kerry ran. 

If there is a GB for this, I like to state my interest for an assembled board option like the last one Kerry ran. 

GB.

http://www.head-case.org/forums/topic/12282-group-buy-digital-attenuator-kevin-gilmore/

Edited August 16, 201510 yr by b0bb

GB.

http://www.head-case.org/forums/topic/12282-group-buy-digital-attenuator-kevin-gilmore/

Doh! Thanks!  Don't know how I missed that one.

Interest added to the spreadsheet.

 

 

Edited August 16, 201510 yr by mwl168

I tested the board out and it works perfectly

I needed some time to figure out just how to program it, but I got it working now.

Edited August 16, 201510 yr by Kerry
Text didn't show up

the production board will be 2.0 inches wide, reduced from 2.05 inches wide

so that the input/output jacks line up perfectly.

i can also change the hole size to #4 if people want.

Edited August 17, 201510 yr by kevin gilmore

I like #4 for this board better, but either would work for me.

the production board will be 2.0 inches wide, reduced from 2.05 inches wide

so that the input/output jacks line up perfectly.

i can also change the hole size to #4 if people want.

#4 works for me. Thanks.

#4 it is, new file posted v42

which is actually 4.2 but I'm lazy

Is possible add Tachyonix's control chip as option to control volume with next version PCBs?

http://www.tachyonix.co.jp/english.shtml

http://www.tachyonix.co.jp/3310ir01e.pdf

http://www.tachyonix.co.jp/3310srevA.pdf

Thanks!

Edited November 25, 201510 yr by palchiu

those are designed for cs3310 and not for anything else that i'm aware of

19 hours ago, kevin gilmore said:

those are designed for cs3310 and not for anything else that i'm aware of

Dear kevin,

Thank you!

I'm not electrical guy, just imagine if something can make controller part more simply.

Pal